\documentclass{article}
\usepackage{amssymb,amsmath,amscd,concmath}
\pagestyle{empty}
\begin{document}
\begin{equation*}\lim_{k\rightarrow 0} {\sum_{n=0}^{\infty-k} {\int_{0}^{n} e^{\frac{-1}{2}x^2}\, dx}}\,\end{equation*}
\end{document}
